Use of ULSAB Technologies by Automakers Growing Rapidly

Applications of High-Strength Steel, Tailor Welded Blanks,
Hydroforming and Laser Welding All Are Up

DETROIT, MI, February 16, 2000 — In the nearly
two years since the global steel industry unveiled its UltraLight Steel
Auto Body (ULSAB), the world’s automakers steadily have been
increasing their uses of the advanced steel technologies that ULSAB
demonstrated so effectively.

The primary ULSAB technologies that have been showing up in new
vehicles include high and ultra high-strength steel, tailor welded
blanks, hydroforming and laser welding.

"Car companies don’t want to tip their hands so it has been
difficult for us to learn in advance exactly how our customers are
applying ULSAB technologies," said Darryl C. Martin, senior director,
Automotive Applications, American Iron and Steel Institute (AISI). "But,
we know they are. We see abundant examples of these technologies in the
vehicles they have put on the road since we unveiled ULSAB in March
1998. The feedback we have received — both formal and informal
— has been very encouraging," said Martin.

ULSAB demonstrated that through the use of advanced steels, the
latest in process technologies and holistic engineering, it is possible
to substantially reduce the mass of body structures using steel. Doing
so helps vehicle makers gain all the numerous benefits of steel
including safety, low cost and environmental friendliness, while
reducing emissions and increasing fuel economy.

ULSAB used more than 90 percent high-strength and ultra high-strength
steels, which played a significant role in reducing body weight while
providing excellent crash performance. Examples of current vehicles
using high amounts of high-strength steel include:

The 1999 BMW 3-series has a body structure weighing 230 kg with a
high-strength steel content of 50 percent. The previous model contained
less than 5 percent.

Ford's new Focus uses high-strength steel for both the body
structure and exterior body panels.

The new GM "G" platform (Cadillac DeVille, Buick LeSabre, Pontiac
Bonneville and Oldsmobile Aurora) uses a tailor welded blank for the
body side inner panel, similar to a body side outer panel used in ULSAB.
Use of a tailor welded blank for the body side outer in ULSAB added an
extra challenge to the project because the rear quarter panel is a
visual part.

The GM "G" platform also employs North America’s first
non-linear tailor welded blank applications in the floor pan.
The Volkswagen Golf, the car with the highest number of tailored blanks,
employs 14 to 21 tailored blank parts, depending on the specific
version.

GM’s 2000 full size SUVs incorporate finished blanks that
measure 103 in. by nearly 71 in., the largest tailored units that the
company has ever used.

Nearly all Chrysler platforms now use tailor welded blanks. The Jeep
Grand Cherokee uses nine, four of which are in the body structure.

ULSAB demonstrated an innovative, hydroformed side roof rail that
runs from the A-pillar along the B- and C-pillars into the rear floor
panel. It is a key element in the structure and provides an excellent
load path for structural stiffness and performance in crash. Instead of
using a standard tube with a relatively low diameter to thickness ratio
(D/t), the ULSAB hydroformed roof rail is constructed from a tube with a
diameter of 96 mm and a thickness of 1 mm, resulting in a D/t ratio of
96.

GM has been using hydroforming for a similar roof rail application as
ULSAB in the body structure of such vehicles as the Buick Park Avenue
and Cadillac Seville. Size and location of the roof rail are different
than in ULSAB in that the tubes GM is using are much thicker gauge.

GM also is using this technology for the front part of the main frame
members for the Sierra/Silverado trucks.

Currently, the main application for hydroforming is in engine
cradles, suspension, radiator supports and IP beams, but carmakers are
using more hydroforming in the body-in-white. At the 1999 International
Body Engineering Conference (IBEC), Rover presented a paper on a
hydroformed space frame concept for the Land Rover Freelander. Rover
initiated the project after assessing ULSAB and plans to demonstrate
additional innovative hydroforming for main body structure members.

Laser Welding

The ULSAB body structure features 18 m of laser welding,
approximately 60 percent of which is required to join the hydroformed
side roof rails to the roof. This approach accommodates one-sided access
and enhances the stiffness of the body-in-white.

Volvo began using laser welding for the roof in the 850 (the
predecessor of the V70), followed by other European automakers including
BMW, Volkswagen and Mercedes.

ULSAB extended the use of laser welding to the upper and lower front
rails to enhance crash performance, over an alternative design using
standard spot welding. Instead of using thicker, heavier material,
Porsche Engineering Services elected the innovative approach of
employing laser welding, resulting in a stronger, continuous joint.

The Automotive Applications Committee (AAC) is a subcommittee of the
Market Development Committee of AISI and focuses on advancing the use of
steel in the highly competitive automotive market. With offices and
staff located in Detroit, cooperation between the automobile and steel
industries has been significant to its success. This industry
cooperation resulted in the formation of the Auto/Steel Partnership, a
consortium of DaimlerChrysler, Ford and General Motors and the member
companies of the AAC.

This release and other steel-related information are available for
viewing and downloading at American Iron and Steel Institute/Automotive
Applications Committee’s website at http://www.autosteel.org.